Whip stock removing device



Feb. 8, 1938. ca. KOTHNY WHIP STOCK REMOVING DEVICE Filed Sept. 28, 1937 8 A 4 /mm mm a |v2 Q v l l hqAn 1 &\ & M w m. )2 a 2 4 v 2 7r Asa 5W0? 6'0 fa avail.

m f 7 Vi Patented Feb. 8,1938

UNI-TED STATES PATENT oerce WHIP STOCK REMOVING DEVICE Gottdank L. Kothny, Strafford, Pa., assignor to Sperry-Sun Well Surveying Company, Philadelphia, Pa., a corporation of Delaware Application September 28, 1937, Serial No. 166,064

9 Claims.

' This invention relates to a device for removing whipstocks from bore holes and, more particularly, to a device adapted to be included within a drill string above the bit for effecting such result.

For the purpose of producing deviations of bore holes from their original directions, whipstocks are frequently used for guiding drill bits in directions sloping with respect to the original bore hole axes. In certain cases such whipstocks are arranged to be permanently located in the bore hole by being cemented therein. In other cases, however, the whipstocks are made removable so that they may be removed and re-used, their presence in the bore hole after drilling of a deviating extension being generally unneces-' sary inasmuch as subsequent drilling will follow the path of the portion of the borehole drilled by the tool.which was originally deviated by the whipstock. While a removable whipstock may be recovered by a fishing operation following removal of the drill string, considerable time may be saved by removing the whipstock with the drill string. A proposal has been made to effect such removal by causing the drill bit to engage a collar on the upper end of a whipstock to pull it from the hole when the drill string is raised. The use of such a device, however, is not always whipstock from the position' in which satisfactory because it precludes the removal of the drill string to replace a worn or broken bit without the simultaneous removal of the whipstock.

It is the general object of'the present invention to provide means whereby the whipstock may be removed from the bore hole with the drill string but need not necessarily be removedwith the drill string, so that the latter, if need arises, may be removed from the bore hole to replace a bit or for other purposes w le, the whipstock rem'ainsin its original position to serve for the guidance of another hit.

This and subsidiary objects of the invention will become apparent from the following description read in conjunction with the accompanying drawing in which:

Figure 1 illustrates a section of a bore hole and shows in elevation a whipstock secured to a drill stern in position for location inthe bore hole;

Figure 2. is a similar section, but showing the relationship of the whipstock and drill string following the drilling of a deviated hole and prior to removal of the whipstock; I

Figure 4 is a transverse section taken on the plane indicated at 4-4 in Figure 3.

Referring first to Figure 1, there is illustrated therein a whipstock 2 of substantially conventional character, provided with a concave sloping 5- bit guiding surface 4 and awedge-shaped lower end 6 arranged to be driven into the soil at the bottom of a bore hole. The whipstock is provided at its upper end with a collar 8 having an opening sufiiciently large to pass a drill bit I2. 10

This drill bit or'a collar of similar outside diameter located above it on the drill stem I0 is arranged to be secured to the collar a shear pin Hi. This pin .ll is made sufficiently strong so that before it is sheared off by the weight of the drill stringthe whipstock 2 will.be

' driven sufiiciently far into the earth at the bottom of the bore hole to hold it securely during the drilling operation and also prevent its removal without the application of substantial upward force to the drill string. Before it is driven into the bottom of the bore hole, the whipstock may be oriented in any conventional'fashion.

It will benoted that the upper end of the drill bit is tapered -,,to insure that it 'may be lifted freely through the collar 8 without exerting any such force on the collar as would tend to lift the it is fixed. Consequently,'with the arrangement described. drilling mayproceed as indicated in Figure'2 and the bit may be removed and reinse'rtedin the bore hole as often as desired without eflecting removal of the whipstock.

Located "a a suitable polntabove the-bit, im'- mediately' above it if it is desired that the whipstock should hauled out of the bore hole ex- \tending below the bit, or substantially above the bit if the whipstock is to be hauled out above the bit, is a lower section l8 of the drill stem which desirably has a diameter approximately that of the drill bit so as to' pass through the collar 8 with a fairly close fit, its'lower end being tapered to insure free passage. This section l8 of the drill stem is provided with longitudinal slots 20 within which are pivoted at 24 members 22 normally held within the perimeter of the section l8 by leaf springs 28 secured, as indicated at 28, to the section l8. Preferably, the springs 26 and the members 22 rather closely fit the walls of the slots 20 to prevent to a considerable extent leakage of the circulating mud at this point so that it is forced through the usual passages in the drill stem to the bit. A small amount of leakage .at this point, however, is not harmful.

When it is desired to'remove. the whipstock 8 by means of i from the hole, the'drill stem is lowered to such an extent that the element It is below the collar I. When it is in such position, a go-devil Il may be dropped within the drill stem to engage the wedge-shaped portions 2'3 of the members 22 to cam the latter outwardlyand then, by engagement with the tapered .walls 32 of the central passage of the element II, to be retainedin a position between the members 22 with the result that they cannot be forced inwardly by outside pressure. When expanded, themembers 22 will occupy the positions shown in construction lines in Figure 3, below the collar 8, also shown in construction lines in that fi ure. It will be obvious that under these conditions sufllcient force applied to the drill stem will dislodge the whipstock Vice.

K through said collar.

from its position and cause it the drill stem. i

In the .event that the go-devil should be to be raised with dropped and then decision made not to haul out the whipstock by-means of the drill string, the go-devil may beremoved" by means of a catcher engageable with the element 34 located at its upper end. When so removed, the springs 26 will retract the members 2 2 within the perimeter of the element It. e

To provide, free circulation of mud throughout all of the portions described above, suitable grooves may be provided to by-pa'ss the mud both on theinside and outside of the various elements. For example, the grooves 36 serve tolpermit mud to flow by the go-devii 30 when it is in its lowermost position, and grooves 38, running longitudinally of the outside, permit the exterior passage of mud.

It will be clear that the invention may be embodied in various forms other than that speciflcally disclosed. For example, other means than a go-devil may be provided for the purpose of actuating devices to engage a whipstock.

What I claim and desire to protect by Letters Patent is:

1. The combination with a whipstock comprising a body arranged to penetrate the bottom of a bore hole and provided with a sloping drill guiding surface and a collar at the upper portion of the body, of a device arranged to be included in a drill string. said device being arranged to pass through said collar, and being provided with .means expandible outwardly to engage said collar whereby the whipstocl; may be removed from a hole by means of a drill string including said dc- 2. The combination-with a whipstock comprising a body arranged to penetrate the bottom of a bore hole and provided with a sloping drill guid-' 3. The combination with a whipstock comprising a body arranged to penetrate the bottom of a bore hole and provided with a sloping drill guiding surface and a collar at the upper portion of the body, of a device arranged to be included in a drill string, said device being arranged to pass through said collar, and being provided with means expandible outwardly to engage said collar whereby the whipstock may be removed from a hole by means of a drill string including said device, said .expandible means being movable by the dropping of a go-devil to eifect its expansion.

4. Means for effecting removal of a whipstock from a bore hole comprising a body arranged to and means for normally maintaining said expandible means within the perimeter of sai body. v

6. Means for effecting removal ofa whipstock from a bore hole comprising a body arranged to be included in a drill string above the bit and means carried by said body and expandible outwardly to engage and lift a whipstock with the drill stem, said expandible means being movable 'by the dropping of a go-devil to eiiect its expansion. V

7. Means for eflecting removal Voi a whipstock from a bore hole comprising a body arranged to be included in a drill-string above the bit and means carried by 'saidbody andexpandible 'o'utwardly to engage and lift a whipstock with" the drill stem, said means lever pivoted in said body and arrangedto move mprising at least one from a position within the perimeter ofsaidbody to a position outside the same.

8. Means for efiectingremoval of a whipstock from a bore hole comprising a body arranged to be'included in a drill string; above the bit and.

means carried by said .body and expandible outwardly to engage and lift a whipstock ,with the v N drill'stem, said means comprising at least one lever pivoted in said body and arranged to be moved by a go-devil from a position within the perimeter of said body to a position outside the same.

9. Means for effecting removal of a whipstock from a bore hole comprising a body'arranged to be included in a drill string above the bit and means carried by said body and expandible out- GOT'IDANK L. KOTHNY. 

